Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3c561c4d33634d0…

MALICIOUS

PDF

79.9 KB Created: 2021-04-22 13:59:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: c8cff7127217c56027e1e5fa367bb4cc SHA-1: 0b197b87e8bee94943ac1a39df27efd4ccc1aff7 SHA-256: a3c561c4d33634d0ab3c00f3d60877faf5d9907caca0cd51796f39291db0528a
252 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links, many of which point to disposable hosting and redirector infrastructure, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded links, such as 'https://yafferge.ru/strik?utm_term=first+90+days+learning+plan+template', are likely used to redirect users to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://yafferge.ru/strik?utm_term=first+90+days+learning+plan+template In PDF document text
    • http://muxoman.mygamesonline.org/82904434878.pdfIn PDF document text
    • http://kijofizovurisos.medianewsonline.com/hydrogenation_of_alkenes.pdfIn PDF document text
    • https://nilukosezaxed.weebly.com/uploads/1/3/0/8/130814529/0998801c0.pdfIn PDF document text
    • https://waxitajoxozaner.weebly.com/uploads/1/3/4/4/134474673/dufunuwego_nolusoriru.pdfIn PDF document text
    • http://zereteleriw.getenjoyment.net/41325665730.pdfIn PDF document text
    • http://melidagerukebel.sportsontheweb.net/cavite_mutiny_filipino_version.pdfIn PDF document text
    • http://tepifugamokeg.medianewsonline.com/purevpn_server_list.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/feef10a3-cdd3-4fa2-9399-af7d5efb6eec/fazurorekogusa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3768fd2-a423-472c-943d-b6e5b85893ed/the_journal_entry_to_record_the_purchase_of_merchandise_on_account_would_include.pdfIn PDF document text
    • https://s3.amazonaws.com/dabatisew/rimworld_ice_sheet_survival.pdfIn PDF document text
    • https://a91873a8-1f5b-4151-915d-af39eb211f25.filesusr.com/ugd/3f80ec_55a461b4ba9b4b76880731ae02a20d47.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d1c0e4d-f472-404e-a137-babb3b9f5e5c/dusux.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f5ae0c0-5aad-40a1-983a-b5b5686e0c99/the_far_side_of_jericho_full_movie.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d7495d8e-a3c2-4dd8-bec3-b1045ed3763e/92779810450.pdfIn PDF document text
    • https://s3.amazonaws.com/bufipevuril/92207408329.pdfIn PDF document text
    • https://0fc0baf9-b884-4fcd-968e-f93c0f938930.filesusr.com/ugd/68ec51_04e81fb9c1684c55be99e30af1234713.pdf?index=trueIn PDF document text
    • http://bofekid.epizy.com/space_jam_2.pdfIn PDF document text
    • https://ca6b24e6-01cd-4368-a310-1df05077a315.filesusr.com/ugd/11b39a_63f17ae42b774034bf9ddbcc86d4e13e.pdf?index=trueIn PDF document text
    • http://vipuwizu.epizy.com/98417148586.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA58 5632 bytes
SHA-256: f16f463ec7679fbf273952d4f34240d9df58334391651dd143ce37b0371caa5a
font_01_sfnt_off00010d78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D78 10884 bytes
SHA-256: 946c8bc2a9dd4015738efcd2213657cbef9f765f8cdb64260803a692bff731f3